Steam turbine



K. BAUMANN.

STEAM TURBINE.

APPLICATION FILED OCT. 4, I916. RENEWED IAN. 20.1921.

Patented Feb. 7, 1922.

H SHEEI'SSHEET 3.

A rro/m/gys KI BAUIVIANN.

STEAM TURBINE.

APPLICATION FILED OCT. 4. I916. RENEWED IAII. 20,192].

40 5 Patented Feb. 7, 1922.

H SHEETS-SHEET 2.

OM W zm 9 K BAUMANN.

STEAM TURBINE.

APPLICATION FILED OCT. 4, 1916'- RENEWED JAN. 20.1921.

K. BAUMANN.

STEAM TURBINE.

APPLICATION FILED OCT. 4. I916. RENEWED JAN. 20, 21-

9h 9 IN E ,H um FM 8 d! e] t m a P Fig4- E is K. BAUMANN.

STEAM TURBINE.

APPL|CA T10N FILED 0CT.4,1916.-RENEWED JAN. 20. 1921.

Patented Feb. 7, 1922.

11 SHEETS-*SHEET 5.

Fig5.

Fig?

K. BAUMANN.

STEAM TURBINE.

APPLICATION FILED OCT. 4. I916.

RENEWED lAN.20,1921.

Patented, Feb. 7, 1922.

1] SHEETS-SHEET 7- j 0 Q q 0 O m m kpm m m Fi|||L ||||h ||||l 2 w Q m E ATTOF/V/FYZS.

K. BAUMANN.

STEAM TURBINE.

APPLlCATlON EILED OCT. 4. 1916. RENEWED JAN. 20, 1921.

' Patented Feb. 7, 1922.

11 SHEETS-SHEET 8.

ATTORNEYS.

K. BAUMANN..

STEAM TURBINE.

APPLICATION FILED OCT. 4, 1.916- RENEWED. JAN; 20', 1'92].

Patented Feb. 7, 1922.

II SHEETSSHEET 9.

wgfvmwroa' K. BAUMANN. STEAM TURBlNE.

APPLICATION FILED OCT. 4, I916- RENEWED JAN. 20,1921.

Patented Feb. 7, 1922.

H SHEETS-SHEET 1G- K BAUMANN.

STEAM TURBINE. APPLICATION FILED OCT. 4,.-I9.I6. RENEWED JAN. 20. 1921.

1,405,565. v Patented Feb. 7, 1922.

H $HEETSSHEET 11.

MQW

surface of the eonderser to the UNITED STATES PATENT OFFICE.

KA RL BAUMANN, OF URMSTON, ENGLAND, ASSIGNOR TO THE BRITISH WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY LIMITED.

STEAM- TURBINE.

Specification of Letters Patent.

Patented Feb. '7, 1922.

Application filed October 4, 1916, Serial No. 123,697. Renewed January 20, 1921. Serial No. 438,760.

To all whom it may concern:

Be it known that I, KARL BAUMANN, a citizen of the Confederation of Switzerland, and'a resident of Urmston, in the county of Lancaster, England, have invented a new and useful Improvement in or Relating to Steam Turbines, of which the following is a specification. i

This invention relates to steam turbines of the axial flow type, and, although not limited in this respect, is especially ap-- plicable to turbines of this type in'which the steam is led away to the exhaust outlet of the turbine from a plurality of. rows of moving blades.

It is one of the objects of this invention to,

the turbine is uniformly .distributed over alarge area of the condensing surface of the condenser. In the case of a surface condenser for example, thesteam may be distributed over the greaterpart, in some cases substantially the whole of the perimeter of the tube nest, while in the case of a jet condenser the steam may be distributed equally over the whole number of jets employed.

In this way the utilization of the condensing greatest possible advantage is ensured.

Afurther object of'the invention is to in crease the strength. and rigidity of the exhause casing so that the turbine may be supported on its foundations from the two ends only of the exhaust casing. With turbines having large exhaust outlets, as at present constructed, it is generally found necessary to support the turbine not only from the ends but also partly from both sides, necessitating the employment of a bed-plate sup- 'rders between the two mam ported on With a turbine having foundation locks.

.its exhaust casing constructed in accordance with the present invention a complete-bedplate isunne'cessary as the turbine may be su ported on sole plates on foundations pro-' 56 vi ed for'the ends only of the exhaust casing. With the improved rigid construction of turbine exhaust of this invention the condenser may in many cases advantageously be suspended direct from the turbine exhaust,

no other support therefor being provided,

and in this way the use of expansion pieces between the turbine and the condenser is;

obviated. In some cases, however, the condenser may in addition be provided with a resilient support.

Still another object of the invention is to reduce the cost of the construction of the exhaust casing of turbines in which the steam is led away to the exhaust from a plurality of rows of moving blades.

constructed In a turbine exhaust casing 1n accordance with this inventlon a suitably curved guide or guides are provided which deflect the whole of the steam leaving the exhaust blades outwardly into an approximately radial direction of flow. The enclosing walls, of the exhaust casing are so formed as to conductthe steam, which has been deflected by the guide or guides aforementioned into an approximately radial direction of flow, to the exhaust outlet or outlets of the turbine or to the condenser or condensers outwardly in a direction substantially transverse to and away from the turbine axis. Guide walls are preferably also provided which divide the steam leaving one or more rows of 'moving exhaust blades into' separate segmental portions. Said guide walls in conjunction with the enclosing walls of the exhaust casing of the turbine; form passages which conduct the several segmental portions of steam to the" exhaustoutlet or outlets of the turbine or tothe condenser or condensers where more than one is used.

Several forms of turbine exhaust constructed in accordance with the presentinventi'on are shown by way of example in the accompanying drawings in which Figure 1 is a front elevation artly in section, Figure 2 an end elevation all being in section on the line IIII of Figure '1, viewed from the right and Figure 3 a plan of a-turbine and its condenser the turbine having an exhaust casing constructed in accordance with this invention.

Figure 4.- is a central longitudinal section of a turbine cylinder. Figure 5 a cross section taken as re ards its left-hand portion on the live V--- of Figure 4 and as regards its right-hand portion on the line VI-VI of Figure 4 viewed from left to right, Figure 6 a half plan of the lower half of the turbine cylinder, and Figure 7a cross section taken on the line VIIVII of Figure 6 showing another constructional form of an exhaust casing in accordance with this invention.

Figure 8 is a view similar to Figure 1 .and Figure 9 a plan view showing the invention applied to a double flow turbine. The cross sectional view taken on the line VIII--VIII of Figure 8 is similar to the left-hand portion of Figure 2 and is therefore not repeated.

Figures 10 to 17 inclusive'show diagrammatically various other constructional forms which the invention may take.

The same reference numerals are used to indicate like parts in the various figures of the drawings and the arrow heads on the section indicating lines indicate the direction in which the corresponding sectional views are taken.

Referring to Figures 1, 2 and 3, which illustrate an axial flow turbine of the usual construction wherein the steam is led away to the condenser from a single row of moving exhaust blades, the turbine cylinder is indicated at 1, the shaft at 2 and the exhaust casing at 3. The shaft is supported in bearings in pedestals 4, 4 secured to the foundations 5 as usual. The exhaust outlet from the exhaust casing is shown at 6 and directl attached thereto is the condenser 7 here indicated as being of the surface type. The single row of low pressure exhaust blades 8 from which the steam leaves the turbine, is mounted on a wheel 9 on the shaft 2, and in this form of the invention the guide which changes the direction of the flow of steam leaving the exhaust blades from an axial direction into a substantially radial direction, is constituted by a portion 10 ofthe rear' enclosing wall of the exhaust casing which, as will be seen from Figures 1 and 3, is curved and flaring and'resembles somewhat in shape the bell of a trumpet. The exhaust casing 3 is also rovided with guide walls 11 which divide t e steam leaving the row of exhaust blades 8 into a plura ity of segmental portions. Said guide walls extend across the exhaust casing substantially parallel to the turbine axis and may be cast integral with the enclosing walls of the exhaust casing or formed separately and secured thereto by flanges and bolts or otherwise as may be found most convenient, and are here shown as being continued along the exhaust casing until they reach the exhaust connection or outlet 6 of the turbine. These guide walls and also the outer side or boundary wall 12 of the exhaust casing,are sha ed for the greater part of their length to evo ute curves. The 'unction with the enc osing walls of the exust casing of the turbine forma number ide walls 11 in con of separate passages, each of which conducts a segmental portion of the steam leaving the moving blades 8 to the exhaust outlet 6 of the: turbine. The guide walls 11, or"some of them, need not necessarily be continued, as shown, till they reach the exhaust outlet as in some cases they may be discontinued after the point is reached at which portions of steam in adjacent passages are flowing in substantially the same direction. Preferably, however for a purpose hereinafter explained, they are continued, as shown down to the exhaust outlet 6.

As will be seen, the exhaust outlet has the form of a wide and short opening located transversely to the shaft of the turbine and may conveniently be of approximately the same length as the tube nest of the condenser. lVith this construction the steam leaving the moving blades and flowing through the passages formed by the guide walls and the exhaust casing 3 of the turbine, is distributed over approximately the whole length of the condenser and the condensing surface is thus utilized to the greatest possible advantage.

An exhaust casing constructed as above described and shown in Figures 1, 2 and 3, and especially in those cases in which the guide walls 11 are carried down to the exhaust outlet 6, may, by making the walls 11 of suflicient thickness, be made so strong and rigid as to enable the turbine to be supported from feet located atthe two ends only of the exhaust casing, namely transversely of the turbine axis. The supporting feet are indicated at 13, 14 and are preferably cast integral with the lower half'of the exhaust casing in the usual way, and resteithe directly or on sole plates on the foundations 5. The supportingfeet 13 and 14 may advantageously be strengthened by transverse stiffening webs 15 indicated in dotted lines in Figure 3, preferably formed, as" shown, as continuations of the guide walls 11.

The exhaust casing constructed as above described will in many cases be sufliciently rigid to enable the condenser 7 to'be suspended direct from the turbine exhaust outlet 6 as shown in Figures 1 and 2, no other support therefor belng necessary, thus obviating the use of expansion pieces between the turbine and the condenser. In some cases, however, it may be found desirable to provide in addition a resilient support for the condenser.

Figures 4 to 7 inclusive show a modified construction in which the axial'length ofthe exhaustcasing parallel with the turbine axis is increased and its width reduced. The form of the exhaust casing of the turbine and of the supporting feet therefor ,is also varied somewhat from that shown in Figures 1 to 3. As will be seen from an inspection of the left hand portion of Figure somewhat different from that shown in Figures 1 to 3 and their size is also increased. In this construction the supporting feet 14 serve to support the bearing at the exhaust end of the rotor of the turbine thus obviating the use of a separate bearing pedestal.

As will be seen from Figure 7 the shape of the lower half of the exhaust casing and the supporting feet is that of a girder the greatest strength of which is found in the centre where the bending moment is a maximum. As shown in Figure 5 the outer portions of the lower half of the exhaust casing are made separately. This will be found advantageous as it enables the size of the castings to be kept within reasonable limits and also enables metal of suitable qualityto be used for these portions and otherwise to be constructed of sufficient strength to carry the centre portion of the turbine casing as well'as the condenser if desired, the supporting feet in this construction not being extended beneath the high pressure end of the turbine cylinder.

Figures 8 and 9 show the invention applied to a double flow turbine, in which the steam leaving the two final rows of exhaust blades at the middle of the turbine flows in opposite directions. In this case a guide 16 is provided for changing the direction of fiow of the steam leaving the final rows of moving blades 8, 8 from an axial into a substantially radial direction. Otherwlse the construction is substantially the same as that described with respect to Figures 1 to 3 and will be understood without further description. The cross section taken on the line VIII'VIII of Figure 8 will be similar to the left-hand portion of Figure 2.

The invention is especially useful'when applied to multi 1e exhaust turbines, that is axial flow turblnes in which the steam flows in substantially the same direction from a plurality of rows of exhaust blades, a turbine of this kind being described for example: in the specification of Patent No. 1,302,282, dated April 29, 1919, and reissued as No. 15,092, dated April 26, 1921, and the application ofrthe invention to a turbine of this type constitutes the subject-matter of my application Serial No. 404,147, filed August 17, 1920, which is a d1v1s1on of this application.

Figures 10 to 14 inclusive show diagrammatically several other constructional forms of the present invention which may. be

adopted.

In Figure 10 the steam from the moving exhaust blades of the turbine is delivered to two condensers the axes of which are located erpendicular to that of theturbine axis and inclined to the horizontal as shown. This provides a very convenient and suitable arrangement for turbines designed to have a large output the condensers being particularly well located to enable cleaning, inspection or repairs to be carried out with facility.

Figure 11 showsa very similar arrangement to that illustrated in Figure 10 in which, however, the two condensers are placed horizontally.

Figure 12 illustrates another somewhat similar arrangement in which, however, the condensers are installed in a perpendicular position.

Figure 13 indicates still another arrangement in which two separate condensers are employed but with their axes parallel with thatof the turbine axis, and Figure 14 a similar arrangement in which however, only a single condenser is used. Both. of these latter arrangements are such as to enable the steam leaving'the turbine to be admitted over substantially the whole perimeter of the nest of tubes of the condenser.

Where the steam is delivered to two condensers as shown for example in Figures 11 to 13, passages 40 are provided to allow the exhaust steam from the turbine to flow to either one or other of the condensers to ensure equality of vacuum or to allow oneof the condensers to be shut down for cleaning or repairs without shutting down the whole plant. Passages are preferably also provided where only-one condenser is employed to allow the several segmental portions of exhaust steam to escape through the atmospheric relief valve in case the turbine has, for any reason, to be run non-condensing. Usually the freespace between the exhaust outlet and the condenser tubes is suflicient for this purpose. 1

Another form which the exhaust casing may take is shown diagrammatically in Figure 15, Figure 16 being a central vertical section of the exhaust shown in Figure 15,

and Figure 17 a similar view illustrating a e guide and enclosing walls of the ex casing herein described and illustrated are all of them shown as beingprovided with internal guide walls for dividing the steam into segmental portions and forming in conjunction with the exhaust casing separate passages for conducting said portions of steam to the exhaust outlet or outlets, it is to be understood that in many cases some or all of said guide walls may be omitted if desired. In those cases in which all of the guide. walls are omltted the exhaust steam leaving the moving blades will be deflected into an approximately radial direction of flow by the guide or guides provided for that purpose and conducted to the exhaust outlet or outlets or to the condenser or condensers solely by the enclosing walls of the exhaust casing. The

' preferred construction is, however, that in .into an approximately radial direction, the

enclosing walls of said exhaust casing being so formed'as to conduct the radially flowing stream outwardly in substantlally the same transverse plane, and guide walls located within said casing for dividing the exhaust steam into separate streams.

2. A structure such as set forth in claim 1 in which the guide walls for dividing the exhaust into separate streams are shaped to substantially involute curves, along a portion at least of their length.

3. In combination with an axial flow turbine, an exhaust casing so formed as to direct all of the fluid exhausted from the low pressure stage outwardly in substantially radial directions and in substantially the same transverse plane, and partitions withi .therethrough to the turbine in said casing for dividing the fluid passing 7 exhaust into segmental portions.

' R 4; In combination with an axial flow tur- "bine, an exhaust casing so formed as to directthe entire fluid received from the low pressure stage outward-1y in substantially raj dial directions and in substantially the jsame transverse plane,. a dividing wall located within said casing for dividing the [steam .passi d ll in asing area. in the direction bine,:in exhaust casing having a In combination an axial flow tur- Cplurality ofjeircuinferentially extending gui mg, suri ficesarranged in substantially the same transverse {lane for directingthe fluid issuing: froni t the axisof' the turbine and rom an axial a a substantially radial direction of flow,

therethrough into segmental- I portions, sai wall and saidcasing being so constructed as to, form steam passages ,of'

e low pressure stage away fromand a plurality of partitions located within said casing for dividing the fluid passing therethrough into segmental portions.

6. In combination with an axial flow turbine, an exhaust casing for receiving the fluid discharged from the low pressure stage of the turbine, partitions formed within said casing for dividing the interior of the cas ing into segmental passages disposed substantially in the same transverse plane each of which at any given instant serves a segmental section only of the last blades of the low pressure stage, characterized by that said casing and said partitions are so formed that fluid entering the casing is deflected outwardly away from the turbine axis and from an axial direction to a substantially,

the turbine axis and partitions formed within the said casing and dividing the interior thereof into substantially radially extending passages having their discharge openings disposed in substantially the same transverse p ane. I

9. In combination with an axial flow turbine, an exhaust casing receiving the fluid discharged from the low pressure stage and extending substantially radially awayfrom theturbine axis, and partitions formed within the said casing and dividing the interior thereof into substantially radially extending passages having their discharge openings disposed in substantially the same transverse plane and terminating on a substantially longitudinal plane;

10. The combination with a condenser and a turbine having an exhaust casing surrounding a final stage of a turbine provided with a transverse exhaust connection of greater.

length than the width of the exhaust-casing,

of a series of vanes in the casing dividing it into separate, passages adapted to receive fluid from difi'erent sections of the said stage, and dischar e the fluid into the condenser at differentpomtsof the exhaust connection.

11. The'combination with a'condenser and a turbine having an exhaust casing surrounding a final stage of a turbine provided with a transverse exhaust eonnectioxi of greater length than the widtht'o'f the exhaust casing, of a series of varies in the casing'di- ,viding itfinto" separate passages adapted to receive fluidfrom different sections of the said stage, and discharge thefiuid into the condenser at different points along the exhaust' connection. 4

12. The combination with a surface condenser and a turbine having an exhaust casing surrounding a final stage of the turbine and provided with an exhaust connection adapted to discharge fluid exhausted from the said stage into the condenser along substantially the entire length of. the condensing elements, of a series of vanes in the easthe said stage and discharge the fluid/into the condenser at different points along the exhaust connection.

In testimony whereof; I have hereunto subscribed my name this eighth day'of August, 1916.

' KARL BAUMANN. 1 lVitnesses:

C. G. LLOYD, J. D. WALKER. 

